Crankset - does number of teeth matter?

[scotty110788]

Hi, been looking at new cranksets and was just wondering does the amount of teeth matter, if so, what difference does it make?

 

[smokeysmoo]

In a nutshell, the more teeth you have the faster you can go, fitness permitting.
BTW

 

[Smokin Joe]

The more teeth on a chainring the higher the gear ratio. Conversely the more teeth on a sprocket the lower the ratio.

Nip over to Sheldon Brown and do a search for gears for a full explanation.

 

[scotty110788]

In a nutshell, the more teeth you have the faster you can go, fitness permitting.
BTW

thanks now you have created a new question what would average teeth be? I'm looking at a 39/53 one

 

[smokeysmoo]

a 39:53 is commonly referred to as a 'double' and used be the standard. Most new road bikes today are supplied with a 'compact' chainset with a ratio of 50:34. This makes hills more doable yet still gives a decent turn of speed going down the other side as well.

 

[scotty110788]

The more teeth on a chainring the higher the gear ratio. Conversely the more teeth on a sprocket the lower the ratio.

Nip over to Sheldon Brown and do a search for gears for a full explanation.

pure boggled me his site and calculations gonna just count teeth on mine and get something similar thanks

 

[smokeysmoo]

Sheldon has that affect on me too, data overload in most cases, but if you spend some time reading it will start to make sense
I presume we're taking road cranks here are we?

 

[scotty110788]

And what have you got now? Can you move your front mech?

i don't know what i got now, it moves lol just 2 gearscogs atm on front, all i want tbh just want a carbon crankset im still learning bit of the bike at a time

 

[scotty110788]

i have a hybrid boardman

 

[smokeysmoo]

i have a hybrid boardman

Just make sure you get the right BB type. I suspect the Boardman will be a the cartridge type. So a chainset that states BB30 or Hollowtech II for instance won't be suitable.
Is yours worn out? You could just replace the chain rings and save a few quid if your crank arms are ok. If you do this just make sure you get the correct BCD, this is t measurement between the centres of the crank bolt holes, I think yours will be 110mm but I'd definitely check it first as I'm relying on a quick Google.

 

[TheDoctor]

I wouldn't bother getting a carbon chainset on a hybrid.
Lots of cheaper ways of saving some weight.